class User < ActiveRecord::Base
    has_many :microposts, dependent: :destroy
    has_many :relationships, foreign_key: "follower_id", dependent: :destroy
    has_many :followed_users, through: :relationships, source: :followed
    has_many :reverse_relationships, foreign_key: "followed_id", class_name: "Relationship", dependent: :destroy
    has_many :followers, through: :reverse_relationships, source: :follower

    validates :name, presence: true, length: {maximum: 50}
    VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+(\.[a-z]+)*\.[a-z]+\z/i
    validates :email, presence: true, format:{with: VALID_EMAIL_REGEX}, uniqueness:{case_sensitive: true}

    before_save {self.email = email.downcase}

    before_create :create_remember_token

    has_secure_password

    validates :password, length: {minimum: 6}

    def User.new_remember_token
      SecureRandom.urlsafe_base64
    end

    def User.encrypt(token)
      Digest::SHA1.hexdigest(token.to_s)
    end

    def feed
        #Micropost.where("user_id = ?", id)
        Micropost.from_users_followed_by(self)
    end

    def following?(other_user)
        relationships.find_by(followed_id: other_user.id)
    end

    def follow?(other_user)
        relationships.create!(followed_id: other_user.id)
    end

    def unfollow?(other_user)
        relationships.find_by(followed_id: other_user.id).destroy
    end

    private
      def create_remember_token
        self.remember_token = User.encrypt(User.new_remember_token)
      end
end
